<div class="container-fluid">
    <div class="navbar-header">
        <img src="/images/buy.png" alt="" class="logo">
        <a href="" class="title">超市账单管理系统</a>
    </div>

    <div class=" navbar-collapse in" id="bs-example-navbar-collapse-1">
        <a type="submit" class="btn btn-success pull-right btn-login" href="/html/login.html">登录</a>
    </div>
    <div class=" navbar-collapse hidden out" id="bs-example-navbar-collapse-1">
        <a type="submit" class="btn btn-success pull-right btn-logout" href="">注销</a>
        <p class="pull-right loginname">欢迎：<span class="loginusername">admin</span></p>
    </div>
</div>